A conventional ratchet wrench generally includes a head with a driving member rotatably received in a through hole in the head and a handle integrally extends from an end of the head. A control device or a ratchet mechanism is received in a recess defined in an inner periphery of the through hole of the head and includes a pawl, a biasing unit for biasing the pawl and a control bar which is connected to the pawl so as to control the position of the pawl. The pawl can be engaged with toothed outer periphery of the driving member so as to output torque to an object mounted to the driving member, or can be disengaged from the driving member so that the handle can be freely rotated to a desired angle and ready for next rotational movement of the handle. This control device allows the user to reciprocally rotate the object without removing the wrench from the object. However, the parts of the control device are so small so that it is difficult to assemble all the parts in a small recess in the head. Besides, it is difficult to make the recess in a limited area of the head and the manufacturing cost will be high.
The present invention intends to provide a ratchet wrench wherein the control device is easily to be assembled to the head of the wrench.